title: Synthesis of oligosaccharide fragments of the rhamnogalacturonan of Nerium indicum.
abstract: Three trisaccharides, one pentasaccharide, and one heptasaccharide, namely α-D-GalA-(1→2)-α-L-Rha-(1→4)-β-D-GalA-OC3H7 (1), α-L-Rha-(1→4)-α-D-GalA-(1→4)-β-D-GalA-OC3H7 (2), α-D-GalA-(1→4)-α-D-GalA-(1→2)-α-L-Rha-OC3H7 (3), α-D-GalA-(1→2)-α-L-Rha-(1→4)-α-D-GalA-(1→2)-α-L-Rha-(1→4)-β-D-GalA-OC3H7 (4), and α-D-GalA-(1→2)-α-L-Rha-(1→4)-α-D-GalA-(1→2)-α-L-Rha-(1→4)-α-D-GalA-(1→2)-α-L-Rha-(1→4)-β-D-GalA-OC3H7 (5), which are relevant to the fragments of the rhamnogalacturonan of Nerium indicum, were concisely synthesized. The syntheses feature highly stereoselective formation of the α-D-GalA-linkage with GalA N-phenyltrifluoroacetimidates as donors.
authors.affiliation: State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Yuyong
authors.initials: Y
authors.lastname: Ma
authors.forename: Xin
authors.initials: X
authors.lastname: Cao
authors.forename: Biao
authors.initials: B
authors.lastname: Yu
mesh_terms: D002240:Carbohydrate Sequence; D006031:Glycosylation; D006603:Hexuronic Acids / Q000737:chemistry; D007096:Imidoesters / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D030007:Nerium / Q000737:chemistry*; D009844:Oligosaccharides / Q000138:chemical synthesis*; D010368:Pectins / Q000737:chemistry*
chemical_list: D006603:Hexuronic Acids; D007096:Imidoesters; D009844:Oligosaccharides; C473998:rhamnogalacturonan J1; C007819:galacturonic acid; D010368:Pectins
keywords: Glycosyl N-phenyltrifluoroacetimidates; Glycosylation; Nerium indicum; Rhamnogalacturonan; d-Galacturonic acid; l-Rhamnose